Copious numbers of artefacts and books to be put on display and preserved for future generations are kept at museums and archives. Of course, this makes stringent demands of a well controlled indoor climate.

The indoor climate in museums and archives should be kept constant and consistent. Large variations in temperature and ambient humidity can cause condensation or cracking in old books, for example. Organic materials contain microorganisms which can be brought to life by moisture and heat. Dehumidification is also used for preservation of microfilm in order to protect the delicate films.